The present invention relates to a method for producing semiconductor components.
When manufacturing semiconductor components, it is known to produce doped regions in a semiconductor wafer with the aid of ion implantation, gas-phase coating (for example, with diborane or POC13), film diffusion or using liquid solutions.
In contrast, the method of the present invention has the advantage that doped regions with very good homogeneity can be produced. To be regarded as a further advantage is that it is possible, both on the front side and on the back side of the semiconductor wafer, to introduce such homogeneous regions even of different doping types in only one diffusion step. It is also possible to provide different levels of dopant concentration on the front side and back side. The heating of the wafer, and with it, the driving of the doping atoms into the interior of the wafer for producing doped regions at high temperatures in the range of about 1200 to 1280 degrees Celsius advantageously ensures a deep and concentrated penetration of the doping atoms into the wafer.
It is particularly advantageous to coat the wafer surfaces with doping atoms using a chemical vapor deposition method, particularly a chemical vapor deposition method at atmospheric pressure (APCVD, xe2x80x9cAtmospheric Pressure Chemical Vapor Depositionxe2x80x9d). It is thereby possible to achieve extremely high dopant concentrations which reach up to the solubility limit of the silicon wafer.
It is also particularly advantageous to heat the wafer, covered with a glass layer, in oxidizing atmosphere. This advantageously allows the dopant to diffuse into the interior of the wafer in acceptable periods of time.
Furthermore, it is advantageous to cover the glass layer, provided with dopant, with a neutral glass layer prior to the diffusion process. A mutual influencing of the doping of the front side and back side, or of different wafers set up in the diffusion oven at the same time, is thereby reliably prevented.